"We follow the scientists around and look over their shoulders. They're watching their feet: provable mistakes are bad for them. We're looking as far ahead as we can, and we don't get penalized for mistakes."
- Larry Niven

Now the surface was a lethal desert of slag and rolling clouds. Endless clouds drifted back and forth, blotting out the red Sun. Occasionally something metallic stirred, moving through the remains of a city, threading its way across the tortured terrain of the countryside. A leady, a surface robot, immune to radiation, constructed with feverish haste in the last months before the cold war became literally hot.

Leadys, crawling along the ground, moving over the oceans or through the skies in slender, blackened craft, creatures that could exist where no life could remain, metal and plastic figures that waged a war Man had conceived, but which he could not fight himself.